One of the central problems of motivation is the mechanism by which different response topographies reflecting different motivational states are produced by the organism using a common set of effector systems. The solution to this problem would clarify the nature of "behavioral final common path" processes. We plan to approach this problem by examining the manner in which several sets of causal variables interact to determine response topography in the pigeon. The pigeon has been selected for study because the topographies of its eating and drinking responses are distinct both the respect to ingestive behavior (feeding/drinking) and to conditioned responding. Our experiment will provide a quantitative description of the form of ingestive and conditioned responses using a set of common behavioral elements and examine the different sources of control operating in the production of these behaviors. We have developed an electronic/photographic transduction system that allows quantification of such response elements as peck force, duration, location, gape size, eye closure, etc. These elements will be examined for feeding, drinking and conditioned responses generated by autoshaping and operant paradigms. By manipulating stimulus, state and reinforcement variables we will attempt to clarify response topographies and determine their separate contributions to the control of response form. In addition to its conceptual interest for students of motivation and conditioning, the study will provide a behavioral preparation for use in studies of the neural mechanisms by which different modes of organization are imposed upon common muscle groups to generate different behavioral outcomes. Such analyses have hitherto been carried out only with invertebrate species and several features of this preparation make it possible to address this question using physiological and anatomical techniques.